All this makes it natural to regard causation as a relation between facts. For consider what it takes to state a relation 0 between two entities band d, where band d may be facts, particulars, properties or entities of any other kind, and 0 may be any relation: being heavier than, a parent of, next to, etc. Then for any sentence 'Obd' to say that 0 relates b to d, at least two conditions must be met:
(i) 'Obd' must entail that band d exist, since nothing relates anything to nothing; and, since whether or not 0 relates b to d cannot depend on what b or d is called,
(ii) 'Obd' must be transparent for band d. For example, 'Bill is heavier than Kim' can only state a relation between Bill and Kim if it entails their existence and is transparent for them, i.e. its truth value would not be changed by replacing 'Bill' or 'Kim' with any other term for Bill or Kim; and similarly in all other cases. 156
'C causes E', as we have seen, meets both these conditions: (i) it entails the existence of the facts C and E, and (ii) it is transparent for C and E. What more does it take to state a relation between C and E - a relation which, to make 'C causes E' the causal statement it undoubtedly is, must be the relation of causing? Arguably nothing. And if nothing, then does not the fact that C causes E entail that a causal relation holds between C and E?